Need help once again Solved!!
Reply #8 –
You sure it says IAS and not ISA?
Various diagrams and pics in the 2G section at http://fordfuelinjection.com/?p=63
According to them, the above scans, and my diagrams...
"A" (Yellow/white bottom wire) connects to black/orange's fusible link either directly (alternator warning light cars), or via the ammeter+shunt (gauge cars).
"S" (White/black middle wire) connects to the case, one rectifier diode, and middle of the stator (FFI site), or the case and a floating "shield" wire (above).
"I" (Green/red top wire) connects to the alt light (some cars) or directly to the ignition switch (gauge cars) via fusible link "K" (above).
You should be looking for some humongous short circuit that blew your wire right off the fusible link, or overheated it so much it changed color to black before it finally went. Without that wire, there's no "start-up" current to get the alternator charging.